The present invention pertains to a process and a device for collecting empty bottles, especially plastic bottles, and for palletizing the bottles.
EP-0 659 664 A1 shows such a collecting and palletizing device for empty plastic bottles. It comprises a palletizing device, a collecting device arranged upstream of it, and a conveying device arranged between them. The collecting device is connected to a bottle conveyor and is used to transfer the bottles fed in a single row by the bottle conveyor and to arrange them in layers. The collecting device has a circulating rolling belt onto which the bottles are pushed via a funnel-like expansion of the bottle conveyor, wherein the bottles are piled up and are positioned in transverse rows, closing the gaps. The bottles on the rolling belt are pushed by means of profiled pushers to spacers provided on the palletizing unit and are stacked up in layers one after the other by means of an elevator. This collection and palletizing technique is suitable for heavy and stable bottles. In contrast, it cannot be used with sufficient reliability for lightweight plastic bottles, especially so-called PET bottles. These types of bottle are difficult to handle because of their low weight, the electrostatic charge and the high rate of feed by the bottle conveyor.
A similar collecting and palletizing device is also shown in WO 97/11898. The collecting device has a sorting unit here, which joins a two-armed bottle conveyor and comprises a circulating conveyor belt and a plurality of rigid row supports for the bottles. The bottles fed in obliquely by the bottle conveyor move into the row supports one after the other and at the end, forming bottle layers, they enter a pusher, which pushes them off onto a conveyor belt, on which they are moved to the palletizing device with a lifting table.
Furthermore, the conveying of PET bottles by means of pneumatic conveyors has been known in practice. These conveyors have a very complicated design, require much space and are expensive. In addition, considerable problems arise in terms of hygiene.
A filling unit, in which bottles are cleaned, filled with syrup or finished beverages, subsequently closed with caps and then palletized at the end, has been known from EP-0 291 674 A1. Before palletization, the individual bottles are packed in usual bottle carriers. These are either cardboard boxes or plastic carriers. The filled bottles are then conveyed with this packaging to the palletizing device. The packing of the bottles takes place only after the passage through the filling unit. The bottles can be rotated within the filling unit.
The primary object of the present invention is to show a possibility for the operationally reliable handling of even these critical types of bottle.
According to the invention a process is provided for collecting empty bottles, particularly plastic bottles, for palletizing the bottles. The empty bottles are fed in from a bottle producer or a bottle conveyor in one or more rows. The bottles are taken over with at least one upstream collecting device and are later fed to a palletizing device and are palletized there. The empty bottles fed in are transferred at the collecting device onto to one or more intermediate carriers. The carriers form bottles layers. The intermediate carrier with the bottles is subsequently conveyed to the palletizing device.
According to another aspect of the invention, a device is provided for collecting the empty bottles, particularly plastic bottles and for palletizing the bottles. The device has at least one palletizing device with at least one upstream collecting device for taking over the empty bottles being fed in one or more rows from a bottle producer or from a bottle conveyor. A conveying means is arranged between the palletizing and the collecting device. The collecting device has at least one transfer unit and one or more intermediate carriers conveyable with the conveying means for taking up the empty bottles in layers.
The transfer of the bottles onto a conveyable intermediate carrier offers a higher reliability of operation compared with the state of the art and makes possible a plurality of functional variants. This is especially true in regard to the capacity of the plant, which can be increased, storage possibilities and various internal and external carrier circulations. It is particularly advantageous here that the intermediate carrier can stop during the transfer process, which ensures high accuracy of deposition and positioning. The formation of layers on the intermediate carrier makes it possible to commission the bottles according to the pallets and to reach a high palletizing capacity.
For high plant capacity, it is recommended that the collecting device be equipped with a plurality of intermediate carriers and that these be moved to and fro between the transfer unit and the palletizing device in parallel or in circulation. As a result, the transfer unit has no interruptions because of the conveying of the intermediate carriers. It is also favorable to arrange two or more bottle layers corresponding to the pallet size. As a result, the performance capacity is increased further and, in addition, a buffering possibility is created for possible disturbances in operation.
The present invention ensures, preferably by an essentially continuous guiding of the bottles from the row support at the bottle conveyor to the palletizing device, that the bottles will always be in a secured position and can also be accurately positioned. The bottles cannot fall over any more and they cannot cause disturbances in operation. In particular, the device according to the present invention is also able to take up bottles, to transfer them, to arrange them in layers, and to feed the palletizing device on the intermediate carrier at very high feed rates. The device according to the present invention has a very high performance capacity as a result.
It is particularly advantageous that the closing of the row of bottles being fed at laterally spaced locations is also performed with a high reliability. The closing of the row is performed during the transfer within the gripping means by laterally adjustable row grippers. The bottles can then be ultimately arranged in the bottle layer formed on the intermediate carrier in a closely packed arrangement suitable for the ultimate palletization. The device according to the present invention can also be set and changed over for different bottle formats with relatively little effort.
During the transfer or transposition of the rows of bottles, intermediate storage or buffering may be performed by means of a piling table or the like. However, it is also possible to load the gripping means of the transfer unit directly at the bottle conveyors or in the bottle producer and to push the bottles directly into the bottle grippers. This makes possible a very rapid transfer and the very rapid formation of bottle layers.
Railing-like bottle guides, which are adjustable in width, ensure the optimal lateral guiding in the row support. In addition, axial guiding can be brought about in the row supports by means of movable stops driven in a controlled manner, so that the bottles taken over cannot fall over in any direction. The rows can be shifted axially in relation to one another by means of a suitable offset of the stops such that they are arranged with the rows offset so as to fill the gaps in relation to one another and can be packed with maximum density in the bottle layer.
The preferred embodiment of the bottle guide at the intermediate carrier makes it possible to arrange the bottles tightly next to one another and yet to make possible a lateral guiding. This guiding also facilitates the insertion of the rows of bottles on the intermediate carrier and the takeup of the bottle layer on the palletizing device.
The arrangement of a collecting device in the immediate vicinity of a bottle producer makes it possible to eliminate the need for complicated, large pneumatic conveyors with their large space requirement and to make do with short discharge conveyors. As a result, the bottles being produced are taken up very rapidly, transferred and deposited on one or more movable intermediate carriers for further handling.
An individual bottle producer is preferably associated with an individual collecting device each with a capacity coordinated with the bottle production. More collecting devices are correspondingly provided for plants of a higher capacity with a plurality of bottle producers or blowing units. The fault and failure liability during the direct loading of the intermediate carriers at the bottle producer is most extensively minimized in the case of the design according to the present invention. This increases the operational reliability of the entire plant. The question of capacity can be solved by jointly connecting the collecting devices to a common conveying means and especially by arranging an intermediate storage facility for the empty and/or loaded intermediate carriers. This makes it possible to use especially a central palletizing unit for the entire plant and to further reduce the risk of failure. The intermediate storage facility equalizes the different throughputs of the bottle producers and the central palletizing device, on the one hand, and may also be used as a buffer in the case of the failure or disturbance of individual components of the plant, on the other hand. First of all, the bottle produced is uncoupled from any disturbing effects from the area of the palletizing device or the conveying system. The collecting and palletizing device according to the present invention may be expanded into larger bottle handling plants, in which the individual devices may overlap and complement one another. The number and the assignment of the individual components, the collecting device and the palletizing device, can also be adapted in a suitable manner.
The collecting and palletizing device according to the present invention requires relatively little design and control engineering efforts despite a high level of reliability. It also has a small space requirement and can be expanded as desired in the above-mentioned manner. Existing plants can also be retrofitted with it. The collecting and palletizing device according to the present invention is not bound to certain bottle materials or formats, but it can be used for any bottles. Furthermore, it does not require a specially trained operating personnel.
In the preferred embodiment, the intermediate carriers circulate within the bottle handling system and are used to convey the empty bottles layer by layer between the bottle producer and the palletizing device. Moreover, the intermediate carrier may, however, also circulate in a larger circulation by acting as part of the pallet itself and reaching, together with the empty bottles, first the filling plant and farther from there optionally also the customer via the commercial connections. They may optionally also be returned from the customers into the bottle handling system. This form of intermediate carriers with a preferably permanent bottle guiding in the entire circulation facilitates the different bottle handling processes and simplifies the construction efforts and the machinery at the bottle producer, filler and in logistics.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated.